The invention relates to a current distribution system for a vehicle of the type defined in the preamble of claim 1.
A similar type of current distribution system has been described in the Applicants"" international patent applications WO 99/25585 and WO 99/25586. These prior known systems comprise a standard node software, and an individually loadable node configuration which singles out functions controlled by the node software. This very principle is exploited in the present invention in order to enable the building of systems of varying functions on an automated production line, e.g. alongside a vehicle production line, from standard components.
A problem in deploying the above-mentioned prior known systems has proved to be the fact that the vehicle manufacturer may already have a pre-existing intelligent current distribution system in relation to certain system segments, such as a display and the control and diagnostics of an engine and fuel feeding, the intelligent nodes thereof communicating with each other or with a central control unit in accordance with a certain protocol, e.g. a CAN protocol. Generally, however, these systems consist of independent electronic modules, which have nothing to do with each other. In addition to this, a vehicle is usually provided with a multitude of power consuming actuators, such as all lights, motors for windshield wipers and window controls, as well as for sideview mirror controls, rear window defoggers and seat heaters, etc. The information packages used for the control and fault diagnostics of these actuators can be simpler and have a lower frequency than that of the protocol used by vehicle manufacturers, the use of simpler information packages in the system as extensively as possible for the control of power distribution reducing congestion and susceptibility to faults in communication.
Furthermore, it is necessary to reserve a possibility of changes (updates) in the control of power distribution.
It is an object of the invention to provide a power distribution system, wherein a system segment or segments used by a vehicle manufacturer can be integrated as a functional entity with such an intelligent current distribution system which, although provided with a different type of data transfer protocol, controls power distribution to vehicular actuators and which continues to maintain a flexible possibility of producing systems of varying functions.
This object is achieved by the invention on the basis of the characterizing features set forth in the annexed claim 1.
Hence, in a system of the invention, the separate system segments are provided with data transfer protocols different from each other. Thus, the information packages of a first, so-called lower-level data transfer protocol may be sufficiently simple and/or have a low frequency for a reduced susceptibility to faults, while avoiding a congestion of communications in a second, so-called higher-level system segment.
Moreover, the inventive system includes an adapter, which is used for the configuration of at least lower-level nodes and for storing and loading the configuration data. The adapter may also be utilized for the rationalization of production in a higher-level system segment by using the adapter also for the configuration of higher-level intelligent nodes and for storing and loading the node configurations, as will be specified hereinafter.